Merge pull request #79 from EssentialNRG/hotfix/null-ref-capturedevic…

…elock

Fix possible NullReferenceException in CaptureDeviceLock on iOS

BarcodeScanning.Native.Maui/Platform/MaciOS/CameraManager.cs

@@ -356,7 +356,7 @@ private void CaptureDeviceLock(Action action)
                 }
                 finally
                 {
-                    _captureDevice.UnlockForConfiguration();
+                    _captureDevice?.UnlockForConfiguration();
                 }
             }
         });